I can’t not update my phone

See the articles below.

Update your iOS device.        

Get help with over-the-air iOS updates          

Update – Can’t or can’t restore 

Have you tried using iTunes on a computer or Finder if running Catalina or later to do the update?

 Update software on iOS devices in iTunes on Mac

If you see an error when you update or restore your iPhone, iPad, or iPod      

Updating iOS: common issues and solutions

For the best solution please answer the question, Why can you not update your iPhone? Does it come up with an error of some sort? All of this info is needed for an answer to your problem.

Which Model Phone You Have ?

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